Imfinzi Plus Chemotherapy Shows Positive Results for Advanced Biliary Tract Cancer

Phase 3 TOPAZ-1 trial of AstraZeneca’s durvalumab demonstrates an improved overall survival benefit.

Updated results from the TOPAZ-1 (NCT03875235) phase 3 trial showed that durvalumab (Imfinzi; AstraZeneca) in combination with standard-of-care chemotherapy showed clinically meaningful and durable overall survival (OS) benefit as a treatment for individuals with advanced biliary tract cancer.

The findings were presented at the European Society for Medical Oncology Congress 2022 in Paris, France.

“It's exciting to see the improved overall survival delivered by durvalumab plus chemotherapy over the current standard of care for patients with advanced biliary tract cancer after a median follow-up of nearly 2 years. With limited treatment advances over the past decade, these patients have long faced a dismal prognosis,” Do-Youn Oh, MD, PhD, professor of division of medical oncology at the Department of Internal Medicine at Seoul National University Hospital, said in a statement.

“For the first time, an immunotherapy-based combination has shown the ability to alter the course of treatment for this disease and should become the new standard of care,” she said.

The updated results for durvalumab plus chemotherapy (gemcitabine plus cisplatin) showed enhanced efficacy after an additional 6.5 months of follow up, demonstrating a 24% reduction in the risk of death compared with chemotherapy alone.

The updated median OS was 12.9 months compared with 11.3 with chemotherapy.

Additionally, more than 2 times as many individuals were estimated to be alive at 2 years compared with those on chemotherapy alone at 23.6% and 11.5%, respectively.

The findings were seen across all prespecified subgroups, regardless of disease status, programmed death-ligand 1 expression, or tumor location.

The OS benefit was observed in individuals whose tumors stayed the same size, as well as in those whose tumors disappeared or got smaller.

“These longer-term data reinforce the survival benefit and well-tolerated safety profile of [durvalumab] added to standard-of-care chemotherapy for patients with advanced biliary tract cancer. With these results, the exploratory data from the HIMALAYA [NCT03298451] trial and the recent FDA approval based on the TOPAZ-1 trial, we are continuing to advance our commitment to extend survival for patients with gastrointestinal tumors who desperately need new treatment options,” Susan Galbraith, executive vice president of oncology research and development at AstraZeneca, said in the statement.

The safety profile of durvalumab and chemotherapy was well-tolerated, with no new safety signals observed in the longer follow-up. Approximately 60.9% of individuals experienced grade 3 or 4 treatment-related adverse events (AEs) with the combination and 63.5% of individuals receiving chemotherapy alone.

Additionally, durvalumab and chemotherapy did not increase the discontinuation rate, because of AEs compared with chemotherapy alone at 8.9% and 11.4%, respectively.

In September 2022, the FDA granted durvalumab and chemotherapy approval in the United States for individuals with locally advanced or metastatic biliary tract cancer based on results from the TOPAZ-1 trial. It is under review in Europe, Japan, and several other countries.

Reference

Imfinzi plus chemotherapy further improved overall survival benefit in advanced biliary tract cancer in the TOPAZ-1 phase III trial, reducing the risk of death by 24% in additional follow-up. News release. AstraZeneca. September 12, 2022. Accessed September 16, 2022. https://www.astrazeneca.com/media-centre/press-releases/2022/imfinzi-plus-chemotherapy-further-improved-overall-survival-benefit-in-advanced-biliary-tract-cancer-in-the-topaz-1-phase-iii-trial.html